Dial-rim.



No. 857,516- 1 PATENTED JUNE 18, 1907. F. R. CUNNINGHAM. DIAL RIM.

APPLICATION FILED FEB-14. 190s.

5 with the front surface of rim, shown on the line 3,

UNITED STATES PATENT OFFICE.

MASSACHUSETTS.

DIAL-RIM.

Specification of Letters Patent.

Patented June 18, 1907.

Application filed February 14,1906. Serial No. 301,059.

To all whom it may concern.-

Be it known that I, FRANK R. CUNNING- HAM, a citizen of the UnitedStates, and a resident of Medford, in the county of MiddleseX and Stateof Massachusetts, have invented certain new and useful Improvements inDial-Rims, of which the following is a specification.

This invention relates to methods of attaching dials to watch movementswherein a rim surrounding the dial is used; and is in the nature of animprovement on the rim shown in my application filed December 2nd, 1905,Serial N 0. 290,005, method of attaching dials to watch-movements, whereI have shown a rim capable of yielding in a direction toward the edge ofthe dial, but which required attachment to the dial by soldering orsimilar means. y

In the present case the rim holds the dial by spring pressure, yetprovision is made for the rim to yield toward the edge of the dial to sogreat a degree that very close fitting to the movement plate is entirelyobviated.

My invention has for its object to obviate the necessity of soldering,or similarly attaching the rim to the dial, and thus to further theproduction of a cheap, simple and perfect dial fastening.

lVith this end in view, my invention consists in certain novel featuresand details of construction, as hereinafter described. and claimed.

In the accompanying drawings, Figure 1 is an enlarged vertical sectionof the edge of a dial, movement plate and my improved dial 3, of Fig. 1.Fig. 2 1s a similar view showing a modification. Fig. 3 is a plan view(enlarged) showing my improved dial rim of the polygonal form. Fig. 4 isan enlarged plan view of a portion of a dial and movement plate, showingthe dial held by my improved rim.

In Fig. 1 of the said drawings, B represents in section a portion of adial in which 10 is the enamel of the front of the dial, 11 is the copper, and 12 is the enamel of the back of the dial.

A represents in vertical section a portion of the movement plate, inwhich 20 is the front surface against which the back of the dial Brests.

8 is a wall surrounding the movement plate, the top of this wall 8 beingabout level the dial.

13 shows the rim which surrounds the dial.

' This rim is made of spring brass, or other suitable material, and maybe rolled, pressed, spun or drawn up from thin flat stock, no turning orexpensive operations being necessary. The rim when off the dial shouldbe, at the point 13, somewhat smaller than the dial. Then when it isapplied to the dial, it grasps the dials edge with yielding pressure. Aswill be seen, the rim touches the dial only on its flat back surface andat the chamfer between the front surface and the edge. Therefore, afterthe rim is applied to the dial, pressure toward the edge of the dialwill cause the flat portion of the rim which touches the back of thedial, to slide toward the center of the dial, and the rim. being made ofresilient material, it will return to its normal position upon removalof the pressure, as is obvious.

The inner surface of the wall 8 is sloped or undercutan angle of 5 beingfound suitable. The normal diameter of the rim 13 after it is applied tothe dial should be somewhat greater than the inner diameter of the wall8. Then, when the dial B with its rim 13 is pressed within the wall 8,the rim 13 by virtue of its elasticity acting against the illcline ofwall 8, holds the dial safely against the surface 20 of the movementplate A. 9 is an annular groove below the level of surface 20 to provideroom for the flat portion of rim 13.

It is evident that the form of the rim may be varied without departingfrom the spirit of my invention. One variation being shown in Fig. 2which is a vertical section of the same portion of a dial, movementplate and rim as shown in F ig. 1.

As will be seen, the construction shown in Fig. 1 provides a rim capableof yielding toward the edge of the dial to so great a degree that veryclose fitting of the various parts is unnecessary. However, should astill further degree of adjustability be desired. the rims may be madein polygonal form as shown in. Fig. 3. In using this plan the rims maybe normally, before applying to the dial, a loose fit at 13, then ifbent to the form shown in Fig. 3 and applied to the dial it holds thedial securely, the rounded corners 1 1, 15, 16, etc. standing slightlyaway from the edge of the dial. Then, when the dial with this rim ispressed within the wall 8, the visible portion of the rim approximates atrue circle, more or less closely, according to the fit of the severalparts.

Among other advantages secured by my ITO construction are economy inmanufacture, ease and quickness in applying and removing the dial,certainty that the dial cannot become accidentally loosened, and itsdustproof character. WVhen the resilient ring is made perfectlycircular, its dust-proof nature is apparent, inasmuch as it is evidentthat the grip of the rings concave face upon the edge of the dial, andthe pressure of its con vex face against the wall 8 will absolutelyinterfere with the access of dust past the dialedge of the interior ofthe watch. This is not at first sight so clear when the polygonal ringis considered; but when it is noted that the straight sides of the ringas shown in the drawings do not in reality require to be more thanslightly less convex than the remainder in order to produce alternateinternal or centripetal pressure, and external or centrifugal pressure,and, further, that when the parts are put together even this waveringcharacter of the ring is corrected and the ring made circular by the twoconfining surfaces of dial and wall, then the above described dustproofcharacter of the same comes into action. In addition, the pressure ofthe ringedge upon the upper edge or corner of the dial acts to force thelatter down upon its seat on the movement plate, and so cause adust-tight seal between the under surface of the dial and upper surfaceof said plate.

Although I speak of the part 8 as a wall, I do not wish to restrictmyself to its being an absolutely unbroken or uninterrupted struc ture,but I use the term as designating any peripheral projection orprojections rising from the movement plate for confining the ring inplace.

Having thus claim 1. The combination with a movement plate having a wallthereon, of a dial substantially less in diameter than said wall, and aring composed of a flexibly resilient material located between the edgeof said dial and said wall said ring being thinner in cross-section thanthe space between said dial and wall, and held by bending stress inengagement with both dial and wall.

2. The combination with a movement plate having a wall thereon, of adicl substantially described my invention, I

less in diameter than said wall, and a flexibly resilient ring locatedbetween said dial-cdge and wall and curved to grip the dial edge withits top and bottom edges, and to engage said wall with its outer convexface; said ring being thinner in cross-section than the space betweensaid dial and wall.

3. The combination with a movement plate having a wall thereon, of adial substantially less in diameter than said wall, and a flexiblyresilient rim located between said dial edge and wall and curved to gripthe dial edge, one of the inner edges of said rim serving to center saiddial, and the other edge contacting the flat surface of said dial toallow a centripetal yielding of said rim under pressure on its outersurface, said outer surface being adapted to engage the wall on themovement plate.

4. The combination with a movement plate having a wall thereon, and agroove at the foot of said wall, of a dial less in diameter than saidwall, and a ring thinner in cross section than the space between saidwall and dial, and having one edge located in said groove andresiliently engaging both said dial-edge and wall.

5. The combination with a movement plate having a peripheral wall, of adial substantially less in diameter than said wall, and a resilient ringlocated between said dial and wall and engaging both; said ringnorn'ially deviating slightly from the circular form.

6. The combination with a movement plate having an overhung peripheralwall, of a dial substantially less in diameter than said wall, and aresilient ring located between said dial and wall; said ring beingpolygonal in outline.

7. The combination with a movement plate having an overhung peripheralwall, of a dial substantially less in diameter than said wall, and aresilient ring located between said dial and wall; said ring beingconcave-convex in cross section and polygonal in outline.

In testimony whereof I have afl'ixed my signature, in presence of twowitnesses.

FRANK R. CUNNINGHAM.

Witnesses CARRIE S. SLEEPER, LEVINA NELLSON.

